1. Field of the Invention
The present invention is directed to a step assembly which is mounted to a swimming platform in the rear of a watercraft or boat, such as a pleasure boat, and which can be extended and locked when the watercraft or boat is essentially motionless to allow persons to descend into the water or ascend into the watercraft or boat, and which retracts when the watercraft or boat is in forward motion in the water.
2. Brief Description of the Prior Art
Boats and ships are well known in the art. Many boats, primarily motor and sailboats used for pleasure include a swimming platform mounted to the rear of the hull. The swimming platform usually has a horizontal surface unto which a person can step prior to entering the water that floats the boat. Generally speaking, it is difficult for most persons to enter the water directly from the swimming platform and even more difficult, often virtually impossible, for the average person to ascend to the swimming platform from the water. For this reason the prior art provided ladders which can be lowered from the swimming platform into the water and which render it easier for a person to enter into and exit from the water. For several reasons it is usually considered undesirable to leave such ladders in the water when the boat is in motion, therefore the ladder is usually retracted before, or soon after, the boat begins moving. The prior art ladders utilized for this purpose, generally speaking, require extension and retraction by entirely manual operation. This involves manually folding the ladder downward when the ladder is placed into the water and the reverse manual operation when the ladder is retracted.
U.S. Pat. No. 5,427,049 describes a self-retracting ladder assembly to be utilized in connection with personal watercraft. This ladder assembly is mounted underneath the riding platform of the personal watercraft and its surfaces are exposed to the thrust of the water generated by the jet pump. The ladder assembly of U.S. Pat. No. 5,427,049 functions reasonably well when used on personal watercraft powered by a jet pump.
Other step or ladder assemblies used on boats are described in U.S. Pat. Nos. 5,152,244, 5,458,080 and 5,927,433. In spite of the availability of these prior art step or ladder assemblies an improvement of the prior art is needed for boats where the rear of the hull includes a swimming platform. The self-retracting step assembly of the present invention provides such improvement.